Improve getting ffmpeg frame duration

FFmpeg doc says that AVFrame.duration represents the duration
except cases if it's 0 (unknown). It's appeared in only 6.0
so we use a helper to get it.

So let's apply the rule to our AVFrame wrapper.

Pick-to: 6.5
Change-Id: I9596364561f88929796c0097381bfc26bf1d4565
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Lars Knoll <lars@knoll.priv.no>

2 files changed, 19 insertions, 5 deletions

diff --git a/src/plugins/multimedia/ffmpeg/playbackengine/qffmpegframe_p.h b/src/plugins/multimedia/ffmpeg/playbackengine/qffmpegframe_p.h
index 459ceb9b4..e84e0e191 100644
--- a/src/plugins/multimedia/ffmpeg/playbackengine/qffmpegframe_p.h
+++ b/src/plugins/multimedia/ffmpeg/playbackengine/qffmpegframe_p.h
@@ -41,10 +41,13 @@ struct Frame
                 pts = codec.toUs(frame->pts);
             else
                 pts = codec.toUs(frame->best_effort_timestamp);
-            const auto &avgFrameRate = codec.stream()->avg_frame_rate;
-            duration = avgFrameRate.num
-                    ? (1000000 * avgFrameRate.den + avgFrameRate.num / 2) / avgFrameRate.num
-                    : 0;
+
+            if (auto frameDuration = getAVFrameDuration(*frame)) {
+                duration = codec.toUs(frameDuration);
+            } else {
+                const auto &avgFrameRate = codec.stream()->avg_frame_rate;
+                duration = mul(qint64(1000000), { avgFrameRate.den, avgFrameRate.num }).value_or(0);
+            }
         }
         Data(const LoopOffset &offset, const QString &text, qint64 pts, qint64 duration,
              const QObject *source)
diff --git a/src/plugins/multimedia/ffmpeg/qffmpeg_p.h b/src/plugins/multimedia/ffmpeg/qffmpeg_p.h
index 44fd66cf2..ec927f8b5 100644
--- a/src/plugins/multimedia/ffmpeg/qffmpeg_p.h
+++ b/src/plugins/multimedia/ffmpeg/qffmpeg_p.h
@@ -20,6 +20,8 @@ extern "C" {
   (LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(58, 91, 100)) // since ffmpeg n4.3
 #define QT_FFMPEG_HAS_FRAME_TIME_BASE \
   (LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(59, 18, 100)) // since ffmpeg n5.0
+#define QT_FFMPEG_HAS_FRAME_DURATION \
+  (LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(60, 3, 100)) // since ffmpeg n6.0
 
 QT_BEGIN_NAMESPACE
 
@@ -68,7 +70,7 @@ inline void setAVFrameTime(AVFrame &frame, int64_t pts, const AVRational &timeBa
 #endif
 }
 
-inline void getAVFrameTime(AVFrame &frame, int64_t &pts, AVRational &timeBase)
+inline void getAVFrameTime(const AVFrame &frame, int64_t &pts, AVRational &timeBase)
 {
     pts = frame.pts;
 #if QT_FFMPEG_HAS_FRAME_TIME_BASE
@@ -78,6 +80,15 @@ inline void getAVFrameTime(AVFrame &frame, int64_t &pts, AVRational &timeBase)
 #endif
 }
 
+inline int64_t getAVFrameDuration(const AVFrame &frame)
+{
+#if QT_FFMPEG_HAS_FRAME_DURATION
+    return frame.duration;
+#else
+    return 0;
+#endif
+}
+
 struct AVDictionaryHolder
 {
     AVDictionary *opts = nullptr;